H1 antagonists, also called H1 blockers, are a class of medications that block the action of histamine at the H1 receptor, helping to relieve allergic reactions ...

H1-blockers are commonly used to treat the symptoms of allergic reactions. They are found in many over-the-counter products for cold, flu, ...

Generally, they should not be used in older adults or in patients with glaucoma, benign prostatic hyperplasia, constipation, delirium, dementia, or orthostatic ...

Histamine H1 Antagonists ; Ketotifen, A histamine H1 receptor blocker and mast cell stabilizer used to treat mild atopic asthma and allergic conjunctivitis.

H1-blockers are inverse agonists of type 1 histamine (H1) receptors, meaning they preferentially bind to and keep the receptor in the inactive state.

H 1 receptor antagonists (or H 1 -blocking agents) and oppose selectively all the pharmacological effects of histamine except those on gastric secretion.

Sep 18, 2023 · Commonly used H1 antagonists currently available in the United States are cetirizine, levocetirizine, desloratadine, loratadine, and fexofenadine.

Metoprine elevates brain histamine content by blocking the conversion of histamine to methylhistamine. It suppresses food intake, increases water intake.

Jun 21, 2024 · H1 receptor antagonists work by blocking the action of histamine, a chemical released by the body's immune system during an allergic reaction.

Chlorcyclizine which is in the piperazine class of H1-inhibitors was found to elevate intraocular pressure. This effect was prevented by the systemic ...